Hybrid electrically variable powertrains include an engine and a transmission which receives power flow from the engine and from one or more motor/generators. Hybrid electrically variable transmissions have a differential gear set, with power from the engine and power to and from a motor/generator flowing through different members of the differential gear set. Hybrid electrically variable transmissions may include torque-transmitting mechanisms controllable in various engagement schemes to offer a combination of operating modes, including both electrically variable ranges and fixed gear ratios. The electrically variable ranges typically provide optimum engine speed with smooth operation while the fixed gear ratios provide maximum torque performance and maximum fuel economy under certain conditions such as continuous highway cruising. The electrically variable range is established via an electromechanical power path, wherein a fraction of the power transmitted from the engine to the output is converted into electricity by a motor/generator then back into mechanical power by a motor/generator. Fixed gear ratios typically provide excellent transmission output torque and vehicle acceleration by coupling the motor/generators and the engine directly together. In a fixed gear ratio, the power flow path from the transmission input member to the transmission output member is considered to be entirely through a mechanical power path, as speed is not varied by the motor/generator.